OATS: THEIR HISTORY AND HEALTH BENEFITS

by Valentina Caldart

Have you ever wondered what the health benefits of oat milk are? Did you know that drinking it can help you reduce your cholesterol levels? And what about gluten? Can people with celiac disease consume oats, or not?

If you want to learn more about oat nutritional properties, or you’re curious about its origins, this is the article for you!

Oat History

Oat consumption dates back to at least 32 000 years ago. We know this because while exploring a cave in Southern Italy archeologists have found some oat remains on a stone pestle, probably used by paleolithic hunter-gatherers. That was wild oat, though.

Domestication of oat didn’t start until 4000 years ago, but it was only during the first century A.D. that oat fields became widespread all over Europe, thanks to the Romans. Since oat crops grow better in cool climates, their cultivation was particularly successful in Northern Europe, especially in Britain.

In the past, though, oat’s fame wasn’t that good. Pliny the Elder described oat as a degeneration of wheat caused by humidity, and until some decades ago people saw it more as a horse feed rather than a human food. “Oats. A grain, which in England is generally given to horses, but in Scotland supports the people”. That’s how Samuel Johnson defines oat in his Dictionary of the English language, published in 1755. “…And that's why England has such fine horses, and Scotland such fine people”, replied Lord James Boswell, his Scottish biographer.

Even today, only 10% of oats produced globally are consumed by humans, while the rest goes mostly to the animals. Moreover, oats represent only 1.5% of the world’s cereal production, which is dominated by maize, wheat, and rice. That’s a real pity, because oats are nutrient-dense foods that can offer a lot of health benefits.

Health Benefits of Oats

100 grams of oat groats provide around 11 grams of fiber. As you probably know, fiber is fundamental for our gastrointestinal health. It nourishes the good bacteria in our gut, promotes regular bowel movements and reduces colon cancer risk. But hey, it does much more than that: it can help you to lose weight, keep your blood sugar under control and even protect you from heart diseases. Oats are particularly good at it, because they contain a special kind of fiber called “beta-glucan”.

Beta-glucans are water-soluble chains of glucose that we can not digest. On contact with water, they form a viscous gel that slows down the passage of food through the digestive tract. As a consequence, we feel more satiated and we are less likely to eat in between meals. If your dietitian included oats in your weight-loss program, now you know why.

The same viscous gel can also decrease the absorption rate of simple sugars and cholesterol. Try to imagine the inner cavity of your gut loaded with this gelly solution. For amylases, the enzymes that break down starch into sugars, reaching the starch in the oat grains is far more complicated. For us, and especially for people with diabetes, this is really good news. It means that simple sugars are released and absorbed at a lower speed and blood sugar levels don’t spike. Please note that this is particularly true for oat groats and flakes, as in oat milk the starch has already been broken down into simple sugars.

What about cholesterol? It has been shown that consuming 3 grams of oat beta-glucans per day can help reduce LDL cholesterol, an important risk factor for cardiovascular diseases. This happens for two reasons. The first reason is that food cholesterol is “trapped” into the viscous solution formed by beta-glucans and water, hence it’s not efficiently absorbed. The second reason is that blood cholesterol is more easily eliminated by the liver. The liver regularly converts cholesterol into bile acids that are secreted into the gut. These bile acids are usually reabsorbed and recycled, but the beta-glucans gel interferes with this process and promotes their final elimination via feces. If less bile acids are reabsorbed, the liver will use more cholesterol to produce new ones, and your LDL levels will decrease.

One glass of oat milk (250 ml) provides, on average,1 gram of beta-glucans. Consume it with 50 grams of rolled oats in a porridge bowl and you’ll reach your daily dose (3 grams of beta-glucans per day).

Do Oats Contain Gluten?

No, pure oats don’t contain gluten. The storage proteins in oat seeds are different from the ones in wheat, barley, and rye. They don’t contain the same immunogenic fragments and they can’t trigger celiac disease. On the contrary, some studies have shown that celiacs can regularly consume up to 100 grams of oats per day without side effects. But this is true only for uncontaminated oats. This is very important.

Oat is often cultivated and processed along with gluten-containing grains and the risk of contamination is really high. A few grains of wheat in one kilo of oats are enough to contaminate the entire batch, and when the concentration of gluten exceeds 20 ppm (parts per million), the product can’t be marketed as “gluten-free” anymore, because it may provoke adverse reactions in celiac patients.

Research shows that consuming uncontaminated oats can improve both gut wall morphology and quality of life in people with celiac disease. Moreover, compared with rice and corn (which are the most consumed grains in traditional gluten-free diets), oats are a better source of minerals and vitamins and can reduce the risk of developing deficiencies.

Our oat milk is currently NOT gluten-free. If you have celiac disease, don’t drink it. Make sure to buy only oats that are certified “gluten-free”. There are plenty of alternatives out there!

Different Types of Oats

We encourage you to incorporate more oats into your diet, whether it’s in liquid form through our fresh oat milk or in solid forms like oat groats, steel-cut oats, rolled oats or instant oats. If you’re not familiar with these terms, here’s a little guide:

• Oat groats. These are oat seeds in which the inedible outer layer has been removed. Their external layer (the “bran”) is rich in fiber, while the inner layer (the “germ”) is a concentrated source of vitamins, minerals, and healthy fats. They need to be soaked overnight and then cooked for at least 40–45 minutes.

• Steel-cut oats. They’re produced by cutting oat groats with a sharp steel blade, to obtain 2–3 smaller pieces. They still need to be soaked but they cook faster, in 20–30 minutes.

• Rolled oats. Obtained by steam cooking oat groats and flattening them with a roller. The steam softens the seed and enhances its flavour. Rolled oats can be eaten as they are, but it’s better to soak and/or cook them for some minutes, to increase their digestibility and improve the taste.

• Instant oats. Obtained by flattening and grounding pre-cooked oats even more finely. You can eat them “raw” or cook them for 1–2 minutes. They are also available in powdered form.

Okay, now you’re officially an oat expert. Have a glass of oat milk and enjoy the celebrations!

Bibliography

• Menon, R., et al. (2016). Oats-From Farm to Fork. Advances in Food and Nutrition Research, 77, 1-55. https://doi.org/10.1016/bs.afnr.2015.12.001

• The Natural History. Pliny the Elder. John Bostock, M.D., F.R.S. H.T. Riley, Esq., B.A. London. Taylor and Francis, Red Lion Court, Fleet Street. 1855. (link)

• Horton S. Dr. Johnson on Oats. Harper’s Magazine. Published July 2007. Accessed December 4, 2020. https://harpers.org/2007/07/dr-johnson-on-oats/

• Rasane, P., Jha, A., Sabikhi, L., Kumar, A., & Unnikrishnan, V. S. (2015). Nutritional advantages of oats and opportunities for its processing as value added foods – a review. Journal of food science and technology, 52(2), 662–675. https://doi.org/10.1007/s13197-013-1072-1

• Joyce, S. A., Kamil, A., Fleige, L., & Gahan, C. (2019). The Cholesterol-Lowering Effect of Oats and Oat Beta Glucan: Modes of Action and Potential Role of Bile Acids and the Microbiome. Frontiers in nutrition, 6, 171. https://doi.org/10.3389/fnut.2019.00171

• Smulders, M.J.M., et al. (2018). Oats in healthy gluten-free and regular diets: A perspective. Food Research International, 110, 3-10. https://doi.org/10.1016/j.foodres.2017.11